An object is thrown vertically upward at 18m/s from a window and hits the

ground 1.6s later. What is the height of the window above the ground?(air

resistance is negligible)

1 answer

Let h be the window height above ground.

At t = 1.6 seconds,

Elevation y = h + 18t -4.9t^2 = 0
so
h + 28.8 -12.54 = 0

h would be negative. It cannot hit the ground that soon if thrown upaward at that high speed. Recheck you numbers